Commit graph

1503 commits

Author SHA1 Message Date
Sven Eckelmann
a9c4a74ad5 batman-adv: Don't expect inter-netns unique iflink indices
commit 6c1f41afc1 upstream.

The ifindex doesn't have to be unique for multiple network namespaces on
the same machine.

  $ ip netns add test1
  $ ip -net test1 link add dummy1 type dummy
  $ ip netns add test2
  $ ip -net test2 link add dummy2 type dummy

  $ ip -net test1 link show dev dummy1
  6: dummy1: <BROADCAST,NOARP> mtu 1500 qdisc noop state DOWN mode DEFAULT group default qlen 1000
      link/ether 96:81:55:1e:dd:85 brd ff:ff:ff:ff:ff:ff
  $ ip -net test2 link show dev dummy2
  6: dummy2: <BROADCAST,NOARP> mtu 1500 qdisc noop state DOWN mode DEFAULT group default qlen 1000
      link/ether 5a:3c:af:35:07:c3 brd ff:ff:ff:ff:ff:ff

But the batman-adv code to walk through the various layers of virtual
interfaces uses this assumption because dev_get_iflink handles it
internally and doesn't return the actual netns of the iflink. And
dev_get_iflink only documents the situation where ifindex == iflink for
physical devices.

But only checking for dev->netdev_ops->ndo_get_iflink is also not an option
because ipoib_get_iflink implements it even when it sometimes returns an
iflink != ifindex and sometimes iflink == ifindex. The caller must
therefore make sure itself to check both netns and iflink + ifindex for
equality. Only when they are equal, a "physical" interface was detected
which should stop the traversal. On the other hand, vxcan_get_iflink can
also return 0 in case there was currently no valid peer. In this case, it
is still necessary to stop.

Fixes: b7eddd0b39 ("batman-adv: prevent using any virtual device created on batman-adv as hard-interface")
Fixes: 5ed4a460a1 ("batman-adv: additional checks for virtual interfaces on top of WiFi")
Reported-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-03-08 19:09:33 +01:00
Sven Eckelmann
3dae11d21f batman-adv: Request iflink once in batadv_get_real_netdevice
commit 6116ba0942 upstream.

There is no need to call dev_get_iflink multiple times for the same
net_device in batadv_get_real_netdevice. And since some of the
ndo_get_iflink callbacks are dynamic (for example via RCUs like in
vxcan_get_iflink), it could easily happen that the returned values are not
stable. The pre-checks before __dev_get_by_index are then of course bogus.

Fixes: 5ed4a460a1 ("batman-adv: additional checks for virtual interfaces on top of WiFi")
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-03-08 19:09:33 +01:00
Sven Eckelmann
dcf10d78ff batman-adv: Request iflink once in batadv-on-batadv check
commit 690bb6fb64 upstream.

There is no need to call dev_get_iflink multiple times for the same
net_device in batadv_is_on_batman_iface. And since some of the
.ndo_get_iflink callbacks are dynamic (for example via RCUs like in
vxcan_get_iflink), it could easily happen that the returned values are not
stable. The pre-checks before __dev_get_by_index are then of course bogus.

Fixes: b7eddd0b39 ("batman-adv: prevent using any virtual device created on batman-adv as hard-interface")
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-03-08 19:09:33 +01:00
Linus Lüssing
ebe9c978d9 batman-adv: allow netlink usage in unprivileged containers
[ Upstream commit 9057d6c23e ]

Currently, creating a batman-adv interface in an unprivileged LXD
container and attaching secondary interfaces to it with "ip" or "batctl"
works fine. However all batctl debug and configuration commands
fail:

  root@container:~# batctl originators
  Error received: Operation not permitted
  root@container:~# batctl orig_interval
  1000
  root@container:~# batctl orig_interval 2000
  root@container:~# batctl orig_interval
  1000

To fix this change the generic netlink permissions from GENL_ADMIN_PERM
to GENL_UNS_ADMIN_PERM. This way a batman-adv interface is fully
maintainable as root from within a user namespace, from an unprivileged
container.

All except one batman-adv netlink setting are per interface and do not
leak information or change settings from the host system and are
therefore save to retrieve or modify as root from within an unprivileged
container.

"batctl routing_algo" / BATADV_CMD_GET_ROUTING_ALGOS is the only
exception: It provides the batman-adv kernel module wide default routing
algorithm. However it is read-only from netlink and an unprivileged
container is still not allowed to modify
/sys/module/batman_adv/parameters/routing_algo. Instead it is advised to
use the newly introduced "batctl if create routing_algo RA_NAME" /
IFLA_BATADV_ALGO_NAME to set the routing algorithm on interface
creation, which already works fine in an unprivileged container.

Cc: Tycho Andersen <tycho@tycho.pizza>
Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-01-27 10:54:11 +01:00
Linus Lüssing
4c34d5fd8c batman-adv: mcast: don't send link-local multicast to mcast routers
commit 938f2e0b57 upstream.

The addition of routable multicast TX handling introduced a
bug/regression for packets with a link-local multicast destination:
These packets would be sent to all batman-adv nodes with a multicast
router and to all batman-adv nodes with an old version without multicast
router detection.

This even disregards the batman-adv multicast fanout setting, which can
potentially lead to an unwanted, high number of unicast transmissions or
even congestion.

Fixing this by avoiding to send link-local multicast packets to nodes in
the multicast router list.

Fixes: 11d458c1cb ("batman-adv: mcast: apply optimizations for routable packets, too")
Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-01-11 15:25:00 +01:00
Pavel Skripkin
b0a2cd3855 net: batman-adv: fix error handling
commit 6f68cd6348 upstream.

Syzbot reported ODEBUG warning in batadv_nc_mesh_free(). The problem was
in wrong error handling in batadv_mesh_init().

Before this patch batadv_mesh_init() was calling batadv_mesh_free() in case
of any batadv_*_init() calls failure. This approach may work well, when
there is some kind of indicator, which can tell which parts of batadv are
initialized; but there isn't any.

All written above lead to cleaning up uninitialized fields. Even if we hide
ODEBUG warning by initializing bat_priv->nc.work, syzbot was able to hit
GPF in batadv_nc_purge_paths(), because hash pointer in still NULL. [1]

To fix these bugs we can unwind batadv_*_init() calls one by one.
It is good approach for 2 reasons: 1) It fixes bugs on error handling
path 2) It improves the performance, since we won't call unneeded
batadv_*_free() functions.

So, this patch makes all batadv_*_init() clean up all allocated memory
before returning with an error to no call correspoing batadv_*_free()
and open-codes batadv_mesh_free() with proper order to avoid touching
uninitialized fields.

Link: https://lore.kernel.org/netdev/000000000000c87fbd05cef6bcb0@google.com/ [1]
Reported-and-tested-by: syzbot+28b0702ada0bf7381f58@syzkaller.appspotmail.com
Fixes: c6c8fea297 ("net: Add batman-adv meshing protocol")
Signed-off-by: Pavel Skripkin <paskripkin@gmail.com>
Acked-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-11-02 19:48:22 +01:00
Sven Eckelmann
282baa8104 batman-adv: Avoid WARN_ON timing related checks
[ Upstream commit 9f460ae31c ]

The soft/batadv interface for a queued OGM can be changed during the time
the OGM was queued for transmission and when the OGM is actually
transmitted by the worker.

But WARN_ON must be used to denote kernel bugs and not to print simple
warnings. A warning can simply be printed using pr_warn.

Reported-by: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Reported-by: syzbot+c0b807de416427ff3dd1@syzkaller.appspotmail.com
Fixes: ef0a937f7a ("batman-adv: consider outgoing interface in OGM sending")
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-06-23 14:42:41 +02:00
Tetsuo Handa
9a7bc0c403 batman-adv: initialize "struct batadv_tvlv_tt_vlan_data"->reserved field
commit 08c27f3322 upstream.

KMSAN found uninitialized value at batadv_tt_prepare_tvlv_local_data()
[1], for commit ced72933a5 ("batman-adv: use CRC32C instead of CRC16
in TT code") inserted 'reserved' field into "struct batadv_tvlv_tt_data"
and commit 7ea7b4a142 ("batman-adv: make the TT CRC logic VLAN
specific") moved that field to "struct batadv_tvlv_tt_vlan_data" but left
that field uninitialized.

[1] https://syzkaller.appspot.com/bug?id=07f3e6dba96f0eb3cabab986adcd8a58b9bdbe9d

Reported-by: syzbot <syzbot+50ee810676e6a089487b@syzkaller.appspotmail.com>
Tested-by: syzbot <syzbot+50ee810676e6a089487b@syzkaller.appspotmail.com>
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Fixes: ced72933a5 ("batman-adv: use CRC32C instead of CRC16 in TT code")
Fixes: 7ea7b4a142 ("batman-adv: make the TT CRC logic VLAN specific")
Acked-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-04-14 08:41:59 +02:00
Sven Eckelmann
992b03b88e batman-adv: Don't always reallocate the fragmentation skb head
When a packet is fragmented by batman-adv, the original batman-adv header
is not modified. Only a new fragmentation is inserted between the original
one and the ethernet header. The code must therefore make sure that it has
a writable region of this size in the skbuff head.

But it is not useful to always reallocate the skbuff by this size even when
there would be more than enough headroom still in the skb. The reallocation
is just to costly during in this codepath.

Fixes: ee75ed8887 ("batman-adv: Fragment and send skbs larger than mtu")
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
2020-11-27 08:02:55 +01:00
Sven Eckelmann
c5cbfc8755 batman-adv: Reserve needed_*room for fragments
The batadv net_device is trying to propagate the needed_headroom and
needed_tailroom from the lower devices. This is needed to avoid cost
intensive reallocations using pskb_expand_head during the transmission.

But the fragmentation code split the skb's without adding extra room at the
end/beginning of the various fragments. This reduced the performance of
transmissions over complex scenarios (batadv on vxlan on wireguard) because
the lower devices had to perform the reallocations at least once.

Fixes: ee75ed8887 ("batman-adv: Fragment and send skbs larger than mtu")
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
2020-11-27 08:02:55 +01:00
Sven Eckelmann
4ca23e2c20 batman-adv: Consider fragmentation for needed_headroom
If a batman-adv packets has to be fragmented, then the original batman-adv
packet header is not stripped away. Instead, only a new header is added in
front of the packet after it was split.

This size must be considered to avoid cost intensive reallocations during
the transmission through the various device layers.

Fixes: 7bca68c784 ("batman-adv: Add lower layer needed_(head|tail)room to own ones")
Reported-by: Linus Lüssing <linus.luessing@c0d3.blue>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
2020-11-27 08:02:55 +01:00
Taehee Yoo
14a2e551fa batman-adv: set .owner to THIS_MODULE
If THIS_MODULE is not set, the module would be removed while debugfs is
being used.
It eventually makes kernel panic.

Fixes: c6c8fea297 ("net: Add batman-adv meshing protocol")
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
2020-11-15 11:43:56 +01:00
Jakub Kicinski
66a9b9287d genetlink: move to smaller ops wherever possible
Bulk of the genetlink users can use smaller ops, move them.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-10-02 19:11:11 -07:00
Nikolay Aleksandrov
eab3227b12 net: bridge: mcast: rename br_ip's u member to dst
Since now we have src in br_ip, u no longer makes sense so rename
it to dst. No functional changes.

v2: fix build with CONFIG_BATMAN_ADV_MCAST

CC: Marek Lindner <mareklindner@neomailbox.ch>
CC: Simon Wunderlich <sw@simonwunderlich.de>
CC: Antonio Quartulli <a@unstable.cc>
CC: Sven Eckelmann <sven@narfation.org>
CC: b.a.t.m.a.n@lists.open-mesh.org
Signed-off-by: Nikolay Aleksandrov <nikolay@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-09-23 13:24:34 -07:00
David S. Miller
3ab0a7a0c3 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Two minor conflicts:

1) net/ipv4/route.c, adding a new local variable while
   moving another local variable and removing it's
   initial assignment.

2) drivers/net/dsa/microchip/ksz9477.c, overlapping changes.
   One pretty prints the port mode differently, whilst another
   changes the driver to try and obtain the port mode from
   the port node rather than the switch node.

Signed-off-by: David S. Miller <davem@davemloft.net>
2020-09-22 16:45:34 -07:00
Linus Lüssing
2369e82704 batman-adv: mcast: fix duplicate mcast packets from BLA backbone to mesh
Scenario:
* Multicast frame send from BLA backbone gateways (multiple nodes
  with their bat0 bridged together, with BLA enabled) sharing the same
  LAN to nodes in the mesh

Issue:
* Nodes receive the frame multiple times on bat0 from the mesh,
  once from each foreign BLA backbone gateway which shares the same LAN
  with another

For multicast frames via batman-adv broadcast packets coming from the
same BLA backbone but from different backbone gateways duplicates are
currently detected via a CRC history of previously received packets.

However this CRC so far was not performed for multicast frames received
via batman-adv unicast packets. Fixing this by appyling the same check
for such packets, too.

Room for improvements in the future: Ideally we would introduce the
possibility to not only claim a client, but a complete originator, too.
This would allow us to only send a multicast-in-unicast packet from a BLA
backbone gateway claiming the node and by that avoid potential redundant
transmissions in the first place.

Fixes: 279e89b228 ("batman-adv: add broadcast duplicate check")
Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
2020-09-15 10:05:24 +02:00
Linus Lüssing
74c09b7275 batman-adv: mcast: fix duplicate mcast packets in BLA backbone from mesh
Scenario:
* Multicast frame send from mesh to a BLA backbone (multiple nodes
  with their bat0 bridged together, with BLA enabled)

Issue:
* BLA backbone nodes receive the frame multiple times on bat0,
  once from mesh->bat0 and once from each backbone_gw from LAN

For unicast, a node will send only to the best backbone gateway
according to the TQ. However for multicast we currently cannot determine
if multiple destination nodes share the same backbone if they don't share
the same backbone with us. So we need to keep sending the unicasts to
all backbone gateways and let the backbone gateways decide which one
will forward the frame. We can use the CLAIM mechanism to make this
decision.

One catch: The batman-adv gateway feature for DHCP packets potentially
sends multicast packets in the same batman-adv unicast header as the
multicast optimizations code. And we are not allowed to drop those even
if we did not claim the source address of the sender, as for such
packets there is only this one multicast-in-unicast packet.

How can we distinguish the two cases?

The gateway feature uses a batman-adv unicast 4 address header. While
the multicast-to-unicasts feature uses a simple, 3 address batman-adv
unicast header. So let's use this to distinguish.

Fixes: fe2da6ff27 ("batman-adv: check incoming packet type for bla")
Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
2020-09-15 10:05:24 +02:00
Linus Lüssing
3236d215ad batman-adv: mcast: fix duplicate mcast packets in BLA backbone from LAN
Scenario:
* Multicast frame send from a BLA backbone (multiple nodes with
  their bat0 bridged together, with BLA enabled)

Issue:
* BLA backbone nodes receive the frame multiple times on bat0

For multicast frames received via batman-adv broadcast packets the
originator of the broadcast packet is checked before decapsulating and
forwarding the frame to bat0 (batadv_bla_is_backbone_gw()->
batadv_recv_bcast_packet()). If it came from a node which shares the
same BLA backbone with us then it is not forwarded to bat0 to avoid a
loop.

When sending a multicast frame in a non-4-address batman-adv unicast
packet we are currently missing this check - and cannot do so because
the batman-adv unicast packet has no originator address field.

However, we can simply fix this on the sender side by only sending the
multicast frame via unicasts to interested nodes which do not share the
same BLA backbone with us. This also nicely avoids some unnecessary
transmissions on mesh side.

Note that no infinite loop was observed, probably because of dropping
via batadv_interface_tx()->batadv_bla_tx(). However the duplicates still
utterly confuse switches/bridges, ICMPv6 duplicate address detection and
neighbor discovery and therefore leads to long delays before being able
to establish TCP connections, for instance. And it also leads to the Linux
bridge printing messages like:
"br-lan: received packet on eth1 with own address as source address ..."

Fixes: 2d3f6ccc4e ("batman-adv: Modified forwarding behaviour for multicast packets")
Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
2020-09-15 10:05:24 +02:00
Sven Eckelmann
4bba9dab86 batman-adv: Add missing include for in_interrupt()
The fix for receiving (internally generated) bla packets outside the
interrupt context introduced the usage of in_interrupt(). But this
functionality is only defined in linux/preempt.h which was not included
with the same patch.

Fixes: 279e89b228 ("batman-adv: bla: use netif_rx_ni when not in interrupt context")
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
2020-09-14 22:23:24 +02:00
Linus Lüssing
7dda5b3384 batman-adv: mcast/TT: fix wrongly dropped or rerouted packets
The unicast packet rerouting code makes several assumptions. For
instance it assumes that there is always exactly one destination in the
TT. This breaks for multicast frames in a unicast packets in several ways:

For one thing if there is actually no TT entry and the destination node
was selected due to the multicast tvlv flags it announced. Then an
intermediate node will wrongly drop the packet.

For another thing if there is a TT entry but the TTVN of this entry is
newer than the originally addressed destination node: Then the
intermediate node will wrongly redirect the packet, leading to
duplicated multicast packets at a multicast listener and missing
packets at other multicast listeners or multicast routers.

Fixing this by not applying the unicast packet rerouting to batman-adv
unicast packets with a multicast payload. We are not able to detect a
roaming multicast listener at the moment and will just continue to send
the multicast frame to both the new and old destination for a while in
case of such a roaming multicast listener.

Fixes: a73105b8d4 ("batman-adv: improved client announcement mechanism")
Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
2020-09-05 08:45:46 +02:00
Jakub Kicinski
44a8c4f33c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
We got slightly different patches removing a double word
in a comment in net/ipv4/raw.c - picked the version from net.

Simple conflict in drivers/net/ethernet/ibm/ibmvnic.c. Use cached
values instead of VNIC login response buffer (following what
commit 507ebe6444 ("ibmvnic: Fix use-after-free of VNIC login
response buffer") did).

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-09-04 21:28:59 -07:00
Linus Lüssing
097930e85f batman-adv: bla: fix type misuse for backbone_gw hash indexing
It seems that due to a copy & paste error the void pointer
in batadv_choose_backbone_gw() is cast to the wrong type.

Fixing this by using "struct batadv_bla_backbone_gw" instead of "struct
batadv_bla_claim" which better matches the caller's side.

For now it seems that we were lucky because the two structs both have
their orig/vid and addr/vid in the beginning. However I stumbled over
this issue when I was trying to add some debug variables in front of
"orig" in batadv_backbone_gw, which caused hash lookups to fail.

Fixes: 07568d0369 ("batman-adv: don't rely on positions in struct for hashing")
Signed-off-by: Linus Lüssing <ll@simonwunderlich.de>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
2020-08-27 17:41:45 +02:00
Jussi Kivilinna
279e89b228 batman-adv: bla: use netif_rx_ni when not in interrupt context
batadv_bla_send_claim() gets called from worker thread context through
batadv_bla_periodic_work(), thus netif_rx_ni needs to be used in that
case. This fixes "NOHZ: local_softirq_pending 08" log messages seen
when batman-adv is enabled.

Fixes: 23721387c4 ("batman-adv: add basic bridge loop avoidance code")
Signed-off-by: Jussi Kivilinna <jussi.kivilinna@haltian.com>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
2020-08-18 19:40:03 +02:00
Linus Lüssing
d8bf0c0164 batman-adv: Fix own OGM check in aggregated OGMs
The own OGM check is currently misplaced and can lead to the following
issues:

For one thing we might receive an aggregated OGM from a neighbor node
which has our own OGM in the first place. We would then not only skip
our own OGM but erroneously also any other, following OGM in the
aggregate.

For another, we might receive an OGM aggregate which has our own OGM in
a place other then the first one. Then we would wrongly not skip this
OGM, leading to populating the orginator and gateway table with ourself.

Fixes: 9323158ef9 ("batman-adv: OGMv2 - implement originators logic")
Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
2020-08-18 19:40:03 +02:00
Sven Eckelmann
303216e76d batman-adv: Avoid uninitialized chaddr when handling DHCP
The gateway client code can try to optimize the delivery of DHCP packets to
avoid broadcasting them through the whole mesh. But also transmissions to
the client can be optimized by looking up the destination via the chaddr of
the DHCP packet.

But the chaddr is currently only done when chaddr is fully inside the
non-paged area of the skbuff. Otherwise it will not be initialized and the
unoptimized path should have been taken.

But the implementation didn't handle this correctly. It didn't retrieve the
correct chaddr but still tried to perform the TT lookup with this
uninitialized memory.

Reported-by: syzbot+ab16e463b903f5a37036@syzkaller.appspotmail.com
Fixes: 6c413b1c22 ("batman-adv: send every DHCP packet as bat-unicast")
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Acked-by: Antonio Quartulli <a@unstable.cc>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
2020-08-18 19:40:03 +02:00
Sven Eckelmann
0093870aa8 batman-adv: Migrate to linux/prandom.h
The commit c0842fbc1b ("random32: move the pseudo-random 32-bit
definitions to prandom.h") introduced a new header for the pseudo random
functions from (previously) linux/random.h. One future goal of the
prandom.h change is to make code to switch just the new header file and to
avoid the implicit include. This would allow the removal of the implicit
include from random.h

Signed-off-by: Sven Eckelmann <sven@narfation.org>
2020-08-18 19:39:54 +02:00
Sven Eckelmann
21ba5ab2aa batman-adv: Drop repeated words in comments
checkpatch found various instances of "Possible repeated word" in various
comments.

Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
2020-08-18 19:39:54 +02:00
Randy Dunlap
6f5b92a79c batman-adv: types.h: delete duplicated words
Delete the doubled word "time" in a comment.
Delete the doubled word "address" in a comment.

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
2020-08-18 19:39:53 +02:00
Sven Eckelmann
c3b92dd490 batman-adv: Drop unused function batadv_hardif_remove_interfaces()
The function batadv_hardif_remove_interfaces was meant to remove all
interfaces which are currently in the list of known (compatible) hardifs
during module unload. But the function unregister_netdevice_notifier is
called in batadv_exit before batadv_hardif_remove_interfaces. This will
trigger NETDEV_UNREGISTER events for all available interfaces and in this
process remove all interfaces from batadv_hardif_list. And
batadv_hardif_remove_interfaces only operated on this (empty) list.

Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
2020-08-18 19:39:53 +02:00
Simon Wunderlich
426988ee84 batman-adv: Start new development cycle
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
2020-08-18 19:39:53 +02:00
Linus Lüssing
3bda14d09d batman-adv: Introduce a configurable per interface hop penalty
In some setups multiple hard interfaces with similar link qualities
or throughput values are available. But people have expressed the desire
to consider one of them as a backup only.

Some creative solutions are currently in use: Such people are
configuring multiple batman-adv mesh/soft interfaces, wire them
together with some veth pairs and then tune the hop penalty to achieve
an effect similar to a tunable per interface hop penalty.

This patch introduces a new, configurable, per hard interface hop penalty
to simplify such setups.

Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
2020-06-26 10:37:11 +02:00
Sven Eckelmann
bccb48c89f batman-adv: Fix typos and grammar in documentation
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
2020-06-26 10:36:30 +02:00
Simon Wunderlich
d528510e6d batman-adv: Start new development cycle
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
2020-06-26 10:35:06 +02:00
Cong Wang
845e0ebb44 net: change addr_list_lock back to static key
The dynamic key update for addr_list_lock still causes troubles,
for example the following race condition still exists:

CPU 0:				CPU 1:
(RCU read lock)			(RTNL lock)
dev_mc_seq_show()		netdev_update_lockdep_key()
				  -> lockdep_unregister_key()
 -> netif_addr_lock_bh()

because lockdep doesn't provide an API to update it atomically.
Therefore, we have to move it back to static keys and use subclass
for nest locking like before.

In commit 1a33e10e4a ("net: partially revert dynamic lockdep key
changes"), I already reverted most parts of commit ab92d68fc2
("net: core: add generic lockdep keys").

This patch reverts the rest and also part of commit f3b0a18bb6
("net: remove unnecessary variables and callback"). After this
patch, addr_list_lock changes back to using static keys and
subclasses to satisfy lockdep. Thanks to dev->lower_level, we do
not have to change back to ->ndo_get_lock_subclass().

And hopefully this reduces some syzbot lockdep noises too.

Reported-by: syzbot+f3a0e80c34b3fc28ac5e@syzkaller.appspotmail.com
Cc: Taehee Yoo <ap420073@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-06-09 12:59:45 -07:00
David S. Miller
fb8ddaa915 This cleanup patchset includes the following patches:
- Fix revert dynamic lockdep key changes for batman-adv,
    by Sven Eckelmann
 
  - use rcu_replace_pointer() where appropriate, by Antonio Quartulli
 
  - Revert "disable ethtool link speed detection when auto negotiation
    off", by Sven Eckelmann
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Merge tag 'batadv-next-for-davem-20200526' of git://git.open-mesh.org/linux-merge

Simon Wunderlich says:

====================
This cleanup patchset includes the following patches:

 - Fix revert dynamic lockdep key changes for batman-adv,
   by Sven Eckelmann

 - use rcu_replace_pointer() where appropriate, by Antonio Quartulli

 - Revert "disable ethtool link speed detection when auto negotiation
   off", by Sven Eckelmann
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-26 15:19:29 -07:00
Sven Eckelmann
9ad346c905 batman-adv: Revert "disable ethtool link speed detection when auto negotiation off"
The commit 8c46fcd783 ("batman-adv: disable ethtool link speed detection
when auto negotiation off") disabled the usage of ethtool's link_ksetting
when auto negotation was enabled due to invalid values when used with
tun/tap virtual net_devices. According to the patch, automatic measurements
should be used for these kind of interfaces.

But there are major flaws with this argumentation:

* automatic measurements are not implemented
* auto negotiation has nothing to do with the validity of the retrieved
  values

The first point has to be fixed by a longer patch series. The "validity"
part of the second point must be addressed in the same patch series by
dropping the usage of ethtool's link_ksetting (thus always doing automatic
measurements over ethernet).

Drop the patch again to have more default values for various net_device
types/configurations. The user can still overwrite them using the
batadv_hardif's BATADV_ATTR_THROUGHPUT_OVERRIDE.

Reported-by: Matthias Schiffer <mschiffer@universe-factory.net>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
2020-05-26 09:23:33 +02:00
Antonio Quartulli
cf78bb0bbc batman-adv: use rcu_replace_pointer() where appropriate
In commit a63fc6b75c ("rcu: Upgrade rcu_swap_protected() to
rcu_replace_pointer()") a new helper macro named rcu_replace_pointer() was
introduced to simplify code requiring to switch an rcu pointer to a new
value while extracting the old one.

Use rcu_replace_pointer() where appropriate to make code slimer.

Signed-off-by: Antonio Quartulli <a@unstable.cc>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
2020-05-22 14:19:24 +02:00
Sven Eckelmann
2092c910e2 batman-adv: Revert "Drop lockdep.h include for soft-interface.c"
The commit 1a33e10e4a ("net: partially revert dynamic lockdep key
changes") reverts the commit ab92d68fc2 ("net: core: add generic lockdep
keys"). But it forgot to also revert the commit 5759af0682 ("batman-adv:
Drop lockdep.h include for soft-interface.c") which depends on the latter.

Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
2020-05-22 14:19:23 +02:00
Al Viro
38c53ca3c1 batadv_socket_read(): get rid of pointless access_ok()
address is passed only to copy_to_user()

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-05-20 20:31:33 -04:00
David S. Miller
3793faad7b Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Conflicts were all overlapping changes.

Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-06 22:10:13 -07:00
Cong Wang
1a33e10e4a net: partially revert dynamic lockdep key changes
This patch reverts the folowing commits:

commit 064ff66e2b
"bonding: add missing netdev_update_lockdep_key()"

commit 53d374979e
"net: avoid updating qdisc_xmit_lock_key in netdev_update_lockdep_key()"

commit 1f26c0d3d2
"net: fix kernel-doc warning in <linux/netdevice.h>"

commit ab92d68fc2
"net: core: add generic lockdep keys"

but keeps the addr_list_lock_key because we still lock
addr_list_lock nestedly on stack devices, unlikely xmit_lock
this is safe because we don't take addr_list_lock on any fast
path.

Reported-and-tested-by: syzbot+aaa6fa4949cc5d9b7b25@syzkaller.appspotmail.com
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Acked-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-04 12:05:56 -07:00
YueHaibing
e73f94d1b6 batman-adv: remove unused inline function batadv_arp_change_timeout
There's no callers in-tree.

Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
2020-04-24 15:22:41 +02:00
Xiyu Yang
6f91a3f7af batman-adv: Fix refcnt leak in batadv_v_ogm_process
batadv_v_ogm_process() invokes batadv_hardif_neigh_get(), which returns
a reference of the neighbor object to "hardif_neigh" with increased
refcount.

When batadv_v_ogm_process() returns, "hardif_neigh" becomes invalid, so
the refcount should be decreased to keep refcount balanced.

The reference counting issue happens in one exception handling paths of
batadv_v_ogm_process(). When batadv_v_ogm_orig_get() fails to get the
orig node and returns NULL, the refcnt increased by
batadv_hardif_neigh_get() is not decreased, causing a refcnt leak.

Fix this issue by jumping to "out" label when batadv_v_ogm_orig_get()
fails to get the orig node.

Fixes: 9323158ef9 ("batman-adv: OGMv2 - implement originators logic")
Signed-off-by: Xiyu Yang <xiyuyang19@fudan.edu.cn>
Signed-off-by: Xin Tan <tanxin.ctf@gmail.com>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
2020-04-21 10:08:05 +02:00
Xiyu Yang
6107c5da0f batman-adv: Fix refcnt leak in batadv_store_throughput_override
batadv_show_throughput_override() invokes batadv_hardif_get_by_netdev(),
which gets a batadv_hard_iface object from net_dev with increased refcnt
and its reference is assigned to a local pointer 'hard_iface'.

When batadv_store_throughput_override() returns, "hard_iface" becomes
invalid, so the refcount should be decreased to keep refcount balanced.

The issue happens in one error path of
batadv_store_throughput_override(). When batadv_parse_throughput()
returns NULL, the refcnt increased by batadv_hardif_get_by_netdev() is
not decreased, causing a refcnt leak.

Fix this issue by jumping to "out" label when batadv_parse_throughput()
returns NULL.

Fixes: 0b5ecc6811 ("batman-adv: add throughput override attribute to hard_ifaces")
Signed-off-by: Xiyu Yang <xiyuyang19@fudan.edu.cn>
Signed-off-by: Xin Tan <tanxin.ctf@gmail.com>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
2020-04-21 10:08:05 +02:00
Xiyu Yang
f872de8185 batman-adv: Fix refcnt leak in batadv_show_throughput_override
batadv_show_throughput_override() invokes batadv_hardif_get_by_netdev(),
which gets a batadv_hard_iface object from net_dev with increased refcnt
and its reference is assigned to a local pointer 'hard_iface'.

When batadv_show_throughput_override() returns, "hard_iface" becomes
invalid, so the refcount should be decreased to keep refcount balanced.

The issue happens in the normal path of
batadv_show_throughput_override(), which forgets to decrease the refcnt
increased by batadv_hardif_get_by_netdev() before the function returns,
causing a refcnt leak.

Fix this issue by calling batadv_hardif_put() before the
batadv_show_throughput_override() returns in the normal path.

Fixes: 0b5ecc6811 ("batman-adv: add throughput override attribute to hard_ifaces")
Signed-off-by: Xiyu Yang <xiyuyang19@fudan.edu.cn>
Signed-off-by: Xin Tan <tanxin.ctf@gmail.com>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
2020-04-21 10:08:05 +02:00
George Spelvin
fd0c42c4de batman-adv: fix batadv_nc_random_weight_tq
and change to pseudorandom numbers, as this is a traffic dithering
operation that doesn't need crypto-grade.

The previous code operated in 4 steps:

1. Generate a random byte 0 <= rand_tq <= 255
2. Multiply it by BATADV_TQ_MAX_VALUE - tq
3. Divide by 255 (= BATADV_TQ_MAX_VALUE)
4. Return BATADV_TQ_MAX_VALUE - rand_tq

This would apperar to scale (BATADV_TQ_MAX_VALUE - tq) by a random
value between 0/255 and 255/255.

But!  The intermediate value between steps 3 and 4 is stored in a u8
variable.  So it's truncated, and most of the time, is less than 255, after
which the division produces 0.  Specifically, if tq is odd, the product is
always even, and can never be 255.  If tq is even, there's exactly one
random byte value that will produce a product byte of 255.

Thus, the return value is 255 (511/512 of the time) or 254 (1/512
of the time).

If we assume that the truncation is a bug, and the code is meant to scale
the input, a simpler way of looking at it is that it's returning a random
value between tq and BATADV_TQ_MAX_VALUE, inclusive.

Well, we have an optimized function for doing just that.

Fixes: 3c12de9a5c ("batman-adv: network coding - code and transmit packets if possible")
Signed-off-by: George Spelvin <lkml@sdf.org>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
2020-04-21 10:08:04 +02:00
Sven Eckelmann
26893e7e92 batman-adv: Utilize prandom_u32_max for random [0, max) values
The kernel provides a function to create random values from 0 - (max-1)
since commit f337db64af ("random32: add prandom_u32_max and convert open
coded users"). Simply use this function to replace code sections which use
prandom_u32 and a handcrafted method to map it to the correct range.

Signed-off-by: Sven Eckelmann <sven@narfation.org>
2020-04-21 10:07:31 +02:00
Sven Eckelmann
9204a4f876 batman-adv: trace: Drop unneeded types.h include
The commit 04ae87a520 ("ftrace: Rework event_create_dir()") restructured
various macros in the ftrace framework. These changes also had the nice
side effect that the linux/types.h include is no longer necessary to define
some of the types used by these macros.

Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
2020-04-21 10:07:31 +02:00
Sven Eckelmann
c08dd06b3d batman-adv: Fix spelling error in term buffer
checkpatch warns about a typo in the word bufFer which was introduced in
commit 2191c1bcbc64 ("batman-adv: kernel doc for types.h").

Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
2020-04-21 10:07:31 +02:00
Simon Wunderlich
2a7e978625 batman-adv: Start new development cycle
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
2020-04-21 10:07:30 +02:00